/*<stdio.h>
#include<windows.h>
int main()
{
	int i=1;
    double height,pre;
	scanf("%lf",&pre);
	height=pre;
	for(i=2;i<=1000;i=2*i)
	{
		height=height+pre/i;
	}

	printf("%.1f\n",height);
	system("pause");
	return 0;
	
}*/